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000 FXPQ60 PGUM 102150 AFDPQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TIYAN GU 750 AM CHST WED FEB 11 2009 .SYNOPSIS... SHEAR LINE HAS SUNK A BIT FARTHER SOUTH TO AROUND ANATAHAN...WITH SOME MOISTURE POOLING AHEAD OF IT OVER THE FORECAST ZONES THANKS TO SE LOW-LEVEL FLOW. RADAR AND SATELLITE SHOW AREAL COVERAGE AND INTENSITY OF CONVECTION GRADUALLY INCREASING OVER AND AHEAD OF THE SHEAR LINE. RADAR SHOWS LINE OF SHALLOW CONVECTION FROM SOUTHERN GUAM ANGLING NORTHWESTWARD TOWARD THE SHEAR LINE. THIS LINE APPEARS TO BE THE NOSE OF A MODEST SURGE FROM THE SOUTH. CONVECTION SHOWS ENHANCEMENT WHERE THESE BOUNDARIES INTERSECT. && .DISCUSSION... NO MAJOR CHANGES MADE TO THE FORECAST GRIDS. WENT WITH A BLEND OF MODEL SOLUTIONS GIVING MINIMAL WEIGHT TO GFS MASS FIELD SOLUTIONS. GFS IS SUFFERING FROM TOO MUCH CONVECTIVE FEEDBACK... ALTHOUGH REMAIN AT LEAST SOMEWHAT SUSPICIOUS A CIRCULATION MIGHT SPIN UP WHERE THE AFOREMENTIONED BOUNDARIES INTERSECT. AVOIDED TRYING TO BE TOO PRECISE WITH THE WEATHER GRIDS AS SATELLITE IMAGERY SHOWS SOME CONVECTION BREAKING OUT TO THE SOUTH OF THE SHEAR LINE. MODELS ARE STILL SHOWING THE MOST QPF IN THE NORTHERN ZONES...BUT AT LEAST SOME OF THIS IS DUE TO CONVECTIVE FEEDBACK SEEN NEAR THESE LOCATIONS. STILL LOOKS LIKE SHEAR LINE CONVECTION WILL ENTER SAIPAN WATERS TONIGHT AND EXIT GUAM WATERS BY SATURDAY MORNING. TRADE SURGE WILL USHER IN DRIER AIR SUNDAY THROUGH TUESDAY. && .MARINE... TRADE-WIND SURGE IN THE WAKE OF THE SHEAR LINE PASSAGE WILL BRING SMALL CRAFT ADVISORY CONDITIONS FOR COMBINED SEAS BEGINNING ON FRIDAY. SUSTAINED WINDS MAY ALSO MEET THE SMALL CRAFT ADVISORY THRESHOLD. BEST CHANCES FOR THIS APPEAR TO BE FOR TINIAN AND SAIPAN WATERS. A MINIMAL HIGH SURF ADVISORY EVENT FOR EAST FACING EXPOSURES IS ALSO POSSIBLE. && .FIRE WEATHER... KBDI CONTINUES CLIMBING TOWARD 700. PROSPECTS FOR A WETTING RAIN LOOK GOOD BETWEEN NOW AND SATURDAY WITH AT LEAST SOME INTERACTION EXPECTED BETWEEN A PASSING SHEAR LINE AND DEEPER MOISTURE ADVECTING IN FROM THE SOUTH AND SOUTHEAST. SPREAD OF QPF IN THE MODELS REMAINS CONSIDERABLE...SO WHETHER OR NOT A HEAVY RAINFALL EVENT MATERIALIZES REMAINS UNCERTAIN. && .EASTERN MICRONESIA... WEATHER LOOKS FAIRLY QUIET ACROSS THE ISLANDS EXCEPT FOR A TRADE- WIND DISTURBANCE CURRENTLY LOCATED SOUTH OF KOSRAE. DRIER AIR HAS PUSHED IN FROM THE NORTHEAST. ALL SIGNIFICANT TRADE-WIND CONVECTION IS EXPECTED TO PASS SOUTH OF THE FORECAST LOCATIONS DURING THE NEXT FEW DAYS. THE MAIN CONCERN TOWARD THE END OF THE WEEK IS THE WHEN LARGE NW SWELLS ARRIVE. IT MAY BE TOO EARLY TO SPECULATE ON THE SIGNIFICANCE OF THIS EVENT BUT WILL MONITOR THIS SITUATION. WAVE WATCH EXTENDS HAZARDOUS SURF FOR EAST-FACING SHORES ON KOSRAE FOR ANOTHER DAY. THE SURF SHOULD SUBSIDE BELOW ADVISORY HEIGHTS BY THURSDAY MORNING. && .WESTERN MICRONESIA... CONVECTION NORTH AND SOUTH OF PALAU HAS INTENSIFIED DURING THE PAST FEW HOURS. A SURFACE CIRCULATION NORTHWEST OF KOROR WILL CONTINUE TO DRIFT TOWARDS MINDANAO. HOWEVER...A SURFACE TROUGH EXTENDING NORTHEASTWARD FROM KOROR AND YAP WILL ACT AS A FOCUS FOR SCATTERED SHOWERS AND TSTMS ACROSS THE ISLANDS FOR THE NEXT FEW DAYS. ON CHUUK...A MODEST TRADE-WIND DISTURBANCE ARRIVING FROM THE EAST-SOUTHEAST WILL USHER IN SCATTERED SHOWERS TONIGHT AND THURSDAY. A SHORT-LIVED NNW SWELL ON CHUUK IS CAUSING SURF JUST BELOW THE HIGH SURF THRESHOLD. SURF ON NORTH FACING EXPOSURES IS EXPECTED TO SUBSIDE THROUGH FRIDAY TO 7 TO 8 FT. ANOTHER NNW SWELL IS PROGGED TO ARRIVE BY LATE SUNDAY AND IS WORTH WATCHING FOR THE NEXT FEW DAYS. OTHERWISE...SIGNIFICANT SWELLS ARE NOT EXPECTED DURING THE NEXT FEW DAYS. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ MCELROY/BAQUI